Peer-to-peer (“P2P”) communication systems allow the user of a personal computer (“PC”), to engage in voice communication (calls) across a computer network such as the Internet. These systems are beneficial to the user as they are often of significantly lower cost than traditional telephony networks, such as fixed line or mobile cellular networks. This may particularly be the case for long distance calls. These systems utilise voice over internet protocol (“VoIP”) over an existing network (e.g. the Internet) to provide these services, although alternative protocols can also be used. To use a peer-to-peer call service, the user must install and execute client software on their PC. The client software provides the VoIP connections as well as other functions such as registration and authentication. A call may be made using VoIP in accordance with methods known in the art, such as disclosed in WO 2005/009019.
Some calls in a peer-to-peer communication service may be free to the user, such as calls to other users of the same peer-to-peer service. There are therefore significant advantages to the user of the P2P communication service compared to traditional fixed or mobile services. However, the user is constrained by the fact that, in order to make or receive calls using a P2P communication service, they must have access to a PC. Even if the user does have access to a PC, the user must first switch on the PC before making a call, and consequently wait for it to boot up before the call can be made. Additionally, if the user wishes to receive incoming calls, they must leave the PC switched on, as otherwise calls cannot be received. This has the disadvantage of being inefficient from an energy consumption perspective. Users may also be accustomed to mobility whilst using conventional telephony services, due to the prevalence of cordless phones and mobile cellular networks. With P2P communication services, however, the user's location is restricted to the area directly around the PC running the P2P client software.
Furthermore, P2P communication services cannot currently be used to call emergency numbers (for example 911 in the US, 999 in the UK and 112 in the EU). As a result of this, P2P communication services cannot be used as a replacement for conventional telephony services, as the user must be able to contact emergency services.